Merge pull request #15710 from thibaultfaure/articles/BAEL-7399-Injecting-@Captor-in-Junit-Method-Parameters

BAEL-7399 Code for the Injecting @Mock and @Captor in JUnit5 Method P…

testing-modules/mockito-2/pom.xml

@@ -18,10 +18,17 @@
             <version>${mockito-inline.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-junit-jupiter</artifactId>
+            <version>${mockito.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <properties>
         <mockito-inline.version>4.8.1</mockito-inline.version>
+        <mockito.version>5.9.0</mockito.version>
     </properties>
 
 </project>

testing-modules/mockito-2/src/test/java/com/baeldung/injection/ConstructorInjectionUnitTest.java

@@ -0,0 +1,36 @@
+package com.baeldung.injection;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import java.util.function.Function;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+@ExtendWith(MockitoExtension.class)
+class ConstructorInjectionUnitTest {
+    
+    Function<String, String> function;
+    
+    ArgumentCaptor<String> captor;
+    
+    public ConstructorInjectionUnitTest(@Mock Function<String, String> function, @Captor ArgumentCaptor<String> captor) {
+        this.function = function;
+        this.captor = captor;
+    }
+    
+    @Test
+    void whenInjectedViaArgumentParameters_thenSetupCorrectly() {
+        when(function.apply("bael")).thenReturn("dung");
+        assertEquals("dung", function.apply("bael"));
+        verify(function).apply(captor.capture());
+        assertEquals("bael", captor.getValue());
+    }
+
+}

testing-modules/mockito-2/src/test/java/com/baeldung/injection/MethodParameterInjectionUnitTest.java

@@ -0,0 +1,51 @@
+package com.baeldung.injection;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import java.util.function.Function;
+
+import org.junit.jupiter.api.RepeatedTest;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+@ExtendWith(MockitoExtension.class)
+class MethodParameterInjectionUnitTest {
+    
+    @Test
+    void whenMockInjectedViaArgumentParameters_thenSetupCorrectly(@Mock Function<String, String> mockFunction) {
+        when(mockFunction.apply("bael")).thenReturn("dung");
+        assertEquals("dung", mockFunction.apply("bael"));
+    }
+    
+    @Test
+    void whenArgumentCaptorInjectedViaArgumentParameters_thenSetupCorrectly(@Mock Function<String, String> mockFunction, @Captor ArgumentCaptor<String> captor) {
+        mockFunction.apply("baeldung");
+        verify(mockFunction).apply(captor.capture());
+        assertEquals("baeldung", captor.getValue());
+    }
+    
+    @RepeatedTest(2)
+    void whenInjectedInRepeatedTest_thenSetupCorrectly(@Mock Function<String, String> mockFunction, @Captor ArgumentCaptor<String> captor) {
+        mockFunction.apply("baeldung");
+        verify(mockFunction).apply(captor.capture());
+        assertEquals("baeldung", captor.getValue());
+    }
+    
+    @ParameterizedTest
+    @ValueSource(strings = {"", "bael", "dung"})
+    void whenInjectedInParameterizedTest_thenSetupCorrectly(String input, @Mock Function<String, String> mockFunction, @Captor ArgumentCaptor<String> captor) {
+        when(mockFunction.apply(input)).thenReturn("baeldung");
+        assertEquals("baeldung", mockFunction.apply(input));
+        verify(mockFunction).apply(captor.capture());
+        assertEquals(input, captor.getValue());
+    }
+
+}